certd/packages/libs/lib-jdcloud/src/lib/signers/v2_credentials.js

81 lines
1.9 KiB
JavaScript

var cachedSecret = {}
var cacheQueue = []
var maxCacheEntries = 50
var v2Identifier = 'jdcloud2_request'
var util = require('../util')
module.exports = {
/**
* @api private
*
* @param date [String]
* @param region [String]
* @param serviceName [String]
* @return [String]
*/
createScope: function createScope (date, region, serviceName) {
return [date.substr(0, 8), region, serviceName, v2Identifier].join('/')
},
/**
* @api private
*
* @param credentials [Credentials]
* @param date [String]
* @param region [String]
* @param service [String]
* @param shouldCache [Boolean]
* @return [String]
*/
getSigningKey: function getSigningKey (
credentials,
date,
region,
service,
shouldCache
) {
var credsIdentifier = util.crypto.hmac(
credentials.secretAccessKey,
credentials.accessKeyId,
'base64'
)
var cacheKey = [credsIdentifier, date, region, service].join('_')
shouldCache = shouldCache !== false
if (shouldCache && cacheKey in cachedSecret) {
return cachedSecret[cacheKey]
}
var kDate = util.crypto.hmac(
'JDCLOUD2' + credentials.secretAccessKey,
date,
'buffer'
)
var kRegion = util.crypto.hmac(kDate, region, 'buffer')
var kService = util.crypto.hmac(kRegion, service, 'buffer')
var signingKey = util.crypto.hmac(kService, v2Identifier, 'buffer')
if (shouldCache) {
cachedSecret[cacheKey] = signingKey
cacheQueue.push(cacheKey)
if (cacheQueue.length > maxCacheEntries) {
// remove the oldest entry (not the least recently used)
delete cachedSecret[cacheQueue.shift()]
}
}
return signingKey
},
/**
* @api private
*
* Empties the derived signing key cache. Made available for testing purposes
* only.
*/
emptyCache: function emptyCache () {
cachedSecret = {}
cacheQueue = []
}
}